Studies of the molecular changes that are a consequence of various disease states may ultimately lead to an understanding of the process of disease development and possible prevention of the progression of disease. Along these lines, we are utilizing microarray technology to investigate mechanisms regulating apoptosis. Advances in genomics has allowed for the development of technology where gene expression of thousands of genes may be monitored simultaneously in biological samples. We are currently conducting studies examining the gene expression changes in a variety of cells exposed to apoptotic agents. These basic studies will contribute information that may be useful in the treatment and understanding of some diseases including AIDS and cancer, where apoptosis is a significant contributing component. HIV infection leads to the disease AIDS that is characterized by loss of immune cells. The precise mechanism by which HIV replication leads to cell killing is not known. This may be linked to cellular events involving fas ligand, tumor necrosis alpha or other yet unidentified regulators. We are investigating molecular mechanisms that lead to cell apoptosis using microarrays. This technology should prove insight into pathways or molecules involved in this process. Further understanding of mechanisms underlying cell damage/death may lead to new therapies that will prevent cell killing.